hpc.cam.ac.uk email addresses do not provide new points for the delivery of email, and user email messages are not delivered to any part of Darwin itself. However, email messages can be sent manually from the login nodes (e.g. as a result of a user using the mailcommand), or automatically by the queueing system to a user if job notification messages have been requested.
Example - manual mail from a login node
A Cambridge user xyz123 on a login node wishes to send a quick email to another HPC user (assumed also to be a member of the University), pqr456:
[login-sand1 /home/xyz123]$ mail pqr456
or to someone else not necessarily connected with the HPC:
[login-sand1 /home/xyz123]$ mail someone'at'somewhere.net
In the first case, not specifying a non-local part of the recipient address leads to a default of To: pqr456'at'hpc.cam.ac.uk. In both cases, the message generated appears to beFrom: xyz123'at'hpc.cam.ac.uk; replies or error messages will be returned to xyz123'at'hpc.cam.ac.uk and delivered to the home email address provided to us by the user (not to Darwin).
Please note that email involving Darwin accounts not associated with a current member of the University of Cambridge may work differently.
Automatic email notification for a job submitted to SLURM is set via a directive in the submission script such as:
or equivalently on the command line, as in
sbatch --mail-type=ALL ...other options... filename
where ALL can be replaced by one of BEGIN, END, FAIL, REQUEUE to restrict the types of messages sent (see the sbatch documentation). This option can also be given multiple times.
If the job owner is pqr456, these messages will be sent To: pqr456'at'hpc.cam.ac.uk and From: root'at'hpc.cam.ac.uk (except in the case of external users). In fact they are generated by the SLURM server node; the original message, as well as any replies and errors (neither of which should normally occur), are ultimately received by the University's managed mail domain machinery and forwarded appropriately.